2-t-butyl-5-methyl-4,6-dinitrophenyl carboxylates



United States Patent 3,453,318 2-t-BUTYL-5-METHYL-4,6-DINITRO- PHENYL CARBOXYLATES Max Pianka, St. Albans, England, assignor to The Murphy Chemical Company Limited, Wheathampstead, St. Albans, England, a British company No Drawing. Continuation of application Ser. No. 411,727, Nov. 17, 1964. This application Oct. 21, 1966, Ser. No. 588,624 I Claims priority, application Great Britain, May 5, 1961, 16,508/61; July 14, 1961, 25,656/61; Nov. 20, 1963, 45,818/63; Jan. 28, 1964, 3,624/64 Int. Cl. A01m 9/20; C07c 79/28 US. Cl. 260479 6 Claims ABSTRACT OF THE DISCLOSURE There are provided compounds of the formula (CI-I9 0 NO:

in which R is a methyl group, an alkenyl group containing 2 or 3 carbon atoms, a halogenoalkyl group containing 1 or 2 carbon atoms or a halogeno-alkenyl group containing 2 or 3 carbon atoms and R is a hydrogen atom or a methyl group. These compounds are useful as selective pre-emergence herbicides.

This application is a continuation of application Ser. No. 411,727 filed Nov. 17, 1964 and now abandoned, which application is in turn a continuation-in-part of application Ser. No. 191,347, filed Apr. 30, 1962 and also abandoned.

This invention is concerned with improvements in or relating to herbicides.

I have found that compounds of the general formula:

l lo: (I)

in which R is a methyl group, an alkenyl group containing 2 or 3 carbon atoms, a halogenoalkyl group containing 1 or 2 carbon atoms or a halogeno-alkenyl group containing 2 or 3 carbon atoms and R is a hydrogen atom or a methyl group possess significant selective herbicidal properties.

The term halogeno is used herein to indicate chloro or bromo.

These compounds thus have interesting properties as pre-emergence herbicides because of their exceptional selectivity particularly in the control of weeds in crops of sugar beet, leguminosae and cereals.

According to an embodiment of the invention, therefore, there is also provided a method of controlling weeds in a crop particularly of sugar beet, cereals or leguminosae, which comprises applying an effective amount of a compound of the general Formula I above to soil before the emergence of the crop seedlings or the planting in of the crop.

The pre-emergence herbicides according to the invention may be applied to the soil before, during or after the preparation of the seed bed provided they are not applied 3,453,318 Patented July 1, 1969 s)a N 2 l loz (II) where R has the meaning defined above, or a functional derivative thereof is reacted with an acylating derivative of an acid of the general formula R COOH (III) where R has the above meaning. By a functional derivative of the phenol (II) I mean such derivatives as the corresponding alkali metal phenoxides which react with reagents such as acid halides to give the same product as does the parent phenol (II).

In one convenient method of preparing the carboxylate, the phenol (II) may be reacted with an anhydride or halide of the acid of general Formula III. The halide, when used, is preferably the chloride and the reaction is preferably conducted in the presence of an acid binding agent, e.g. a tertiary base such as pyridine or dimethylaniline. The reaction is conveniently effected in the presence of an inert solvent such as diethyl ether, benzene or tetrahydrofuran.

Another method of preparing the carboxylate comprises reaction of the alkali metal phenoxide with a halide of the acid of general Formula III in solution in an inert organic solvent. Particularly suitable solvents for this reaction are ketones, e.g. acetone.

The phenoxide of (II) may as described above be preformed or, may be formed in situ in the inert organic solvent prior to introduction of the halide by reaction of the parent phenol (II) with a suitable alkali metal compound.

The preparation of the active compounds according to the invention by the reaction of an alkali metal phenoxide with a halide of an acid (IH) is particularly advantageous.

However, another advantageous method comprises the simultaneous reaction of the parent phenol (II) with a halide of the acid (IH) as acylating agent in an inert organic solvent (e.g. a ketone such as acetone) in the presence of a suitable alkali metal compound e.g. an alkali metal carbonate.

The selective herbicides according to the invention can be formulated for use in any desired way. Generally such formulations will include the compound in association with a suitable carrier or diluent. Such carriers may be liquid or solid and designed to aid the application of the compound either by way of dispersing it where it is to be applied or to provide a formulation which can be made by the user into a dispersible preparation.

Liquid preparations thus include preparations of the compound in the form of solutions or emulsions which can be used on their own or be adapted to be made up with water or other diluents to form sprays etc.; in such cases the carrier will usually be a solvent or emulsion base. Generally such preparations will include a Wetting, dispersing or emulsifying agent. Other liquid preparations include aerosols in which the compound is associated with a liquid carrier or propellant.

Solid preparations include dusts and wettable powders, granulates and pellets, and semi-solid preparations such as pastes. Such preparations may include inert solid or liquid diluents such as clays, which may themselves have wetting properties, and/or wetting, dispersing or emulsifying agents; binding and/ or adhesive agents may also be included.

.4 the combined filtrate and washings. In order to eliminate any uncondensed 2-t-butyl-4,6-dinitro-5-methylphenol or its potassium salt, the residual solid was dissolved in benzene (50 ml.) and the benzene solution was washed with four 25 ml. portions of 5% aqueous The herbicides of the invention may be admixed with 5 potassium carbonate, then with two 25 ml. portions of other herbicides e.g. to provide a broader spectrum of water. The benzene solution was then dried over anhyactivity. drous sodium sulphate. On distilling off the benzene a For the better understanding of the invention, the solid remained. This was recrystallised from methanol. following examples are given by way of illustration only. 1 2-t-butyl-4,6-dinitro-5-methylphenyl acetate was obtained In these examples temperatures are given in degrees as pale yellow prisms, M.P. 8687, and weighing 27.1 g. centigrade and parts, unless otherwise stated are by (92% yield). Found: N, 9.4. C H N O requires N, weight. Where parts by weight and parts by volume are 9.4%. mentioned together these are to be taken as having the HERBICIDE TESTS relationship of grams to mls.

. Pre-emergence box tests.-In boxes were sown the fol- PreParat1n' N1trat1On of Lbbutybimethylphenol lowing crops: sugar beet, cabbage, carrots, peas and oats A mixture of nitric acid (d=-1.42) (482.5 ml.) and and the following standard weeds: shepherds purse, fat water (480 ml.) was added over a period of 2% hrs. hen, groundsel, chickweed and annual meadow grass. to a solution of 2-t-butyl-5-methylphenol (492 g.) in 20 P1488 was formulated as follows: 20 g. of this comcarbon tetrachloride (2500 ml.) with stirring. The tempound and 10 g. of a blend of non-ionic and anionic emulperature was maintained by ice-water cooling between sifying agents were made up to 100 ml. with heavy 10 and 31. After the addition was completed, the renaphtha. This solution was diluted with the appropriate action mixture was stirred at 20 for a further hour. The q y of Water and pp to the boxes at a fate of reaction mixture was then filtered from a little solid that 4 lbs. of active compound in 40 gallons of water per acre separated out. The lower organic layer was separated on the day of the W Artificial rain equivalent to from the upper layer. The organic layer was washed A rain was then applied. The effect of this treatment i h water 3 portions f 200 l h) Aft allowing was assessed after 21 days. Complete control was obtained the mixture to stand overnight, further solid that had f the f i g w shepherds p r f h n and separated was filtered off. Carbon tetrachloride (1300 chickweed, and mOde'Yate Control of groundsel- Sugar cc.) was then distilled off under slightly reduced presbeet, P and Oat Seedlings suffered no damage- Good sure f h filt t d h id was l d to 9 residual activity was noted as the boxes were still almost 2-t-butyl-4,6-dinitro-5-methylphenol crystallised out. It clean of Weeds 5 Weeks after treatmentwas filtered off and washed with petroleum, B.P. 40-60. Itweighed 272 and melted CONTROL OF WEEDS IN A SUGAR BEET CROP The filtrate was concentrated by distilling 700 ml. of carbon tetrachloride under slightly reduced pressure. In trials in a sugar beet crop similar results were ob- The residue was cooled to 9 and the 2-t-butyl-4,6- tained with no damage to the sugar beet crop and exceldinitro-S-methylphenol that crystallised out was filtered lent control of fat hen. The control of fat hen and safety off. It weighed 78.5 g. and melted at 92-95 C. Total to sugar beet is an unexpected and striking property of weight of the combined first and second crops of 2-t-butylthis 'compound since both these species belong to the 4,6-dinitro-5-methylphenol was 350.5 g. (Found: N, 10.9. family Chenopodiaceae. This property is economically Calculated for C H N O N, 11.0%). Chichibabin & most useful as fat hen is a common weed occurring in Bestuzhev, Bull. soc. chim., 1937, 4 (5) 439 reported sugar beet plantations.

M.P. 9698; Albert & Sears, J. Amer. Chem. Soc., 1954, When the active compound was used at half the rate, 76, 4979 reported M.P. 99100. i.e. 2 lbs. per acre very similar control of weeds was obtained, and again complete control of fat hen with no EXAMPLE 1 damage to the sugar beet crop.

2-t-buty1-4,6dinitro-S-methylphenyl acetate was also W y p y acetate formulated as a wettable powder. A 25% wettable powder 2-t-buty1-4,6-dinitro-5methylphenol 25.4 g.), potasof the active compound was made p as s:

Slum Carbonate g) and acetone 25 g. of the active compound was intimately ground with were refluxed for 1 hr. until a clear solution was obtamed. 635 of speswhite (a fine grade of china clay) The acetone was distilled ofi under reduced pressure 0,5 of h i l di lauryl sulphate and the water present was removed from the residual 6 f l i salt fli i sulphonic acid solid by adding benzene (100 ml.) to it and distilling off the benzene and water. The dry potassium salt of 2-t- This was diluted with water and applied as described butyl-4,6-dinitro-5-methylphenol was dissolved in acetone earlier. The following results were obtained at 2 lb. rate (100 ml.) on refluxing and the solution cooled to 0 in per acre; individual weed counts were made:

Shep- Annual Fat Ground- Chrckherds Meadow Sugar Hon scl Weed Poppy Purse Others Grass Beet ftlftlifis'rjjjj 13 l3 2? 2? 3% ii 3% 3:?

an ice-salt bath. To the solution was added acetyl When propham (common name for the herbicide isochloride (7.95 g.) below 5. The mixture was kept at propyl N-phenylcarbamate) was used in conjunction with 0 for 1% hours, then at room temperature for 16 hours, then refluxed for 2 hrs. The mixture was then cooled, the solid consisting mainly of potassium chloride was filtered off and washed with a little acetone. The

P1488 at the' rate of 2 /2 lbs. of propham and 4 lbs. of P1488 per acre in box tests in addition to the weeds controlled as described above also grasses (annual meadow grass and oats) were killed, and sugar beet and peas were solven w s distilled off under redu ed pr s re from undamaged.

6 The formulation used for the following trials was a Table III summarises the result of counts conducted 50% wettable powder: as before:

TABLE III Field N o. Knotgrass Mayweed pansy of Beet Weed (Polygrmum (Anthemis (Viola beet vigor vigor aviculare) species) arvensz's) P1488 at 2 lbs. per acre.. 428 7. 7 6 88 31 6 P1488 at 1 lb. per acre 395 7 3. 5 30 2 12 PCA at 2.8 lbs. per acre 456 8.2 3. 7 220 6 36 Untreated 455 10 353 17 31 50 parts of the' active compound was intimately ground The results from Sites 1 and 2 demonstrate the efiiciency with 15 of the active compound against fat hen. 43.5 parts of speswhite (a fine grade of china clay) Results from Site 3 demonstrate the activity of P1488 0.5 part of technical sodium lauryl sulphate against knotgrass, an important weed. 6.0 parts of calcium salt of lignin sulphonic acid and diluted with water to give the correct concentration of Results of sugar beet trials in Holland the herbicide.

Trials m Holland were conducted W1th a mixture of RESULTS OF FIELD TRIALS Pl488/end0thal/ and propham. A mixture of 1.4 lbs. In all the tables the quantities of herbicides are in terms endqthal and 1, of 1350p ham acre 18 of actual compounds per acre applied on the black sand type of sod and never glves as high as an 80% control of weeds. However, the mix- SITE 1 ture of Pl488/endothal/propham applied at the rate of 0.45 lb. of P1488, 0.61 lb. endothal, 1.32 lb. of propham per acre gave 80% control of weeds, while PCA applied at 3 /2 lb. per acre gave only 70% control of weeds. Again an excellent control of fat hen was obtained, this being a weed which is not controlled by a mixture of propham and endothal. On a specimen section of the untreated plot 25 fat hens were counted: on the specimen TABLE I section of the treated plot there was only 1 fat hen.

On clay soil on which a mixture of 2.8 lb. of endothal O t 1 if t Fat hen g f f g g i and 2.34 lb. of propham per acre gives less than 60% The site was sown with sugar beet seeds on 9th April and the herbicides applied on 14th April as an overall spray at 50 gallons per acre. The results from counts 30 of fat hen on the four randomised blocks are shown in Table I, each figure being from 2,000 square inches, for fat hen assessments.

Hen albu7n)porcenfi control of cleavers (Galium aparine), the mixture of P1l48/endothal/propham applied at the rate 0.75 lb./1 P14 tllb. 64 2 P1432 t ibe fii ife 14 36 lb./2.2 lb. respectively gave 70% control of this Weed. gjommemalherbmldel 323 9 40 Also an equivalent control of Matricaria sp. and Polygntreated 352 A {W1 d th 1N f d d 7 onum persrcarza to that of enthal/propham mixture mixture) 4 name M 111m was obtained even though the combined weight of l22,ht -2,-d 1t d1 l.f h. bmyc 1] 6p we 3 malboxya e) an A bs 0 prop am P1l48/endothal/propham was lower than that of the The sugar beet was unalfected. endothal/propham mixture.

SITE 2 EXAMPLE 2 The Site Was SOWH with Sugar beet seeds on 30th April 2-t-buty1-4,6-dinitro-5-methylphenyl-a-chloroacetate and the herbicides applied on 1st May in a similar manner to Site 1. The principal weed at this site was fat hen This compound was prepared as in the case of Example with three other weed species present to some degree. The 1 except that chloroacetyl chloride was used. 2-t-butylresults from counts on the randomised blocks are sum- 4,6-dinitro-5-methylphenyl-chloroacetate was obtained as marised in Table II. Each figure was taken from 2,000 pale yellow prisms, M.P. 8'889.5 (from ethanol; 69% square inches for weed assessments and 1,000 square yield) (Found: Cl, 10.7; N, 8.3. C H ClN O requires inches for beet assessment. CI, 10.7; N, 8.5%

TABLE II Fat hen Knotgrass Henbit (Oheno- Groundsel (Polt g- (Lamt'u'm No. of Beet Weed podium (Senecio tmum amplezi- Herbicide Beet vigor vigor album) vulgaris) avz'culare) caule) P1488 1 lb. per acre 301 8. 0 6. 7 130 12 21 P1488 2 lbs. per acre 406 8. l 5. 7 42 4 43 47 P1488 4 lbs. per acre 354 7. 9 2. 7 10 3 19 27 PCA 2.8 lbs. per acre, 375 7. 8 9. 3 266 5 39 39 Commercial Herbicide 2 423 7. 5 7. 0 248 6 17 29 Untreated 385 10 10 337 26 34 76 1 PCA is the abbreviation for the commercial herbicide 5-amino-4-chloro-2-phenyl-3-pyridazone. 2 As in Table I, footnote 1.

SITE 3 7 This was formulated as follows: 10 g. of the active This site was sown with sugar beet seeds on 7th April, compound and 20 g. of a polyethylene glycol ether were and the herbicides were applied on the following day in made up to ml. with acetone. This was applied in a a similar manner to Site 1. The principal weed at this pre-emergence box test as described in Example 1. It site was knotgrass, fat hen being almost absent, and other showed similar activity against weeds, with practically no weeds being present only to a small degree. 7 damage to sugar beet and no damage to pea seedlings.

7 EXAMPLE 3 2-t-butyl-4,6-dinitro-5-methylphenyl acrylate 2-t-butyl-4,6-dinitro-5-methylphenol (7.62 g.) and potassium carbonate (2.5 g.), in acetone (50 ml.), were heated under reflux for 30 min. The acetone was then removed under reduced pressure. To the residue benzene (50 ml.) was added and the benzene and water formed during the reaction were slowly distilled off. The solid residue was dissolved in acetone (50 ml.). To the solution cooled to acrylyl chloride (2.72 g.) was added. The mixture was allowed to stand for 17 hr., then heated under refiux for 1 hr. 10 min. The precipitated potassium chloride was filtered off and the acetone was removed from the filtrate under reduced pressure. The residue was dissolved in benzene (50 ml.) and the benzene solution was washed twice with aqueous 1 N-sodium carbonate solution, then with water, and dried over anhydrous sodium sulphate. After filtration the benzene was removed from the filtrate under reduced pressure. The residue was recrystallised from petroleum (B.P. 60-80"). 2-t-butyl-4, 6-dinitro-5-methylphenyl acrylate was obtained as yellow prisms, M.P. 87-90". (Found: N, 8.9, C H N O requires N, 9.1%).

EXAMPLE 4 2-t-butyl-4,6-dinitro-S-methylphenyl-a-chloro-propionate This was prepared as in Example 3, but using 2-t-butyl- 4,6-dinitro-S-methylphenol (7.62 g.) and ot-chloropropionyl chloride (3.81 g.). On recrystallisation from ethanol with the aid of charcoal 2-t-butyl-4,'6-dinitro-S- methylphenyl a-chloro-propionate was obtained as pale yellow prisms, M.P. 77-78", and weighting 7.64 g. (73.9% yield of theoretical). (Found: N, 8.0. C H ClN O requires N, 8.1%).

EXAMPLE 5 2-t-butyl-4,6-dinitro-S-methylphenyl methacrylate This was prepared as in Example 3, but using Z-t-butyl- 4,6-dinitro-5-methylphenol (7.62 g.) and methacrylylchloride (3.14 g.). On recrystallisation from methanol 2-t-butyl-4,6-dinitro-5-methylphenyl methacrylate was obtained as yellow prisms, M.P. 131-133", and Weighing 7.4 g. (76.6% yield of theoretical). (Found: N, 8.7. C H N O requires N, 8.7%).

The compounds of Examples 3 and 4 were formulated and tested as in Example 1.

5% aqueous sodium carbonate solution. After separation, the organic layer was dried over sodium sulphate, filtered and the solvent distilled off from the filtrate. The solid residue was refluxed for 1 hour with methanol (300 cc.) the solution was decanted off from a part of the solid that did not dissolve. The solution was cooled and the crystallised solid filtered off. The part that did not dissolve was also filtered off. The combined solids were then washed with a little methanol and dried.

2,4-dinitro-6-t-butylphenyl acetate was obtained as pale yellow crystals, weighing 44.7 g. (98.9% of theory) and melting at 134.5l35.5. (Found: N, 9.93. C H N O requires N, 9.94%).

2,4-dinitro-6-t-butylphenyl acetate was formulated as follows: 15 g. of this compound and 20 g. of a blend of nonionic and anionic emulsifying agents were made up to 100 cc. with heavy naphtha. This solution was diluted with the appropriate quantity of water and applied as described.

EXAMPLE 7 2,4-dinitro-6-t-butylphenyl a-chloroacetate 2,4-dinitro-6-t-butylphenol (48 g.), benzene (400 cc.) and pyridine (15.8 g.) were heated to reflux. Chloroacetyl chloride (22.6 g.) was added dropwise, The mixture was then refluxed for 30 mins., then allowed to stand for 16 hrs. at room temperature. Water was added to the mixture to dissolve the precipitated pyridine hydrochloride. The benzene layer was washed several times with water, then it was dried over anhydrous sodium sulphate, filtered and the benzene removed from the filtrate by distillation in vacuo. The residue was then recrystallised from petroleum, B.P. 40-60". 2,4-dinitro- 6-t-butylphenyl chloroacetate was obtained as pale yellow crystals, M.P. 77-79", weighing 29.7 g. (Found: N, 8.80. C H CIN O requires N, 8.85%). 2,4-dinitro-6- t-butylphenyl chloroacetate was formulated as follows: 20 g. of this compound and 20 g. of a blend of nonionic and anionic emulsifying agents were made up to 100 cc. with heavy naphtha. This solution was diluted with the appropriate quantity of water and applied as described.

EXAMPLE 8 2,4-dinitro-6-t-butylphenyl a-chloropropionate This was prepared using the general method of Example 7 from 2,4-dinitro-6-t-buty1phenol and u-ChlOIO- propionyl chloride, 2,4-dinitro-6-t-butylphenyl a-chloropropionate was obtained as a white crystalline solid, M.P.

Weed Crop Annual Product of Shep. Fat Ground- Chick- Meadow c b. Example Purse Hen scl Poppy weed Grass Others Beet bage Carrots Peas Oats 3 at 4 lbs. per acre... P G G N N N 4 5 5 5 5 4 at 2 lbs. per acre... 0 G P 4 5 5 5 Weed control and crop damage are expressed as follows:

Weed control: C=Complete, G=Good, M=Moderate,

P=Poor N=No control Crop damage: 5=No damage, 4=slight damage.

It will be noted that the acrylate had poorer herbicidal activity than the u-chloropropionate, although both were good on fat hen.

5959.5" (from petroleum, B.P. 40-60") (Found: N, 8.50. C13H15C1N206 requires N,

2,4-dinitro-6-t-butylphenyl a-chloropropionate was formulated as follows: 30 g. of this compound and 15 g. of a blend of non-ionic and anionic emulsifying agents were made up to cc. with heavy naphtha. This solution was diluted with the appropriate quantity of water and applied as described.

EXAMPLE 9 2,4-dinitro-6-t-butylphenyl acrylate (P1101) 2,4-dinitro-6-t-butylphenol (36 g.) was dissolved in acetone cc.) anhydrous potassium carbonate (10.8 g., 97% pure) was added and the mixture was refluxed for 1 hour. The acetone was then removed under reduced pressure by distillation. Benzene (150 cc.) was added to the residue and the solution was distilled using a Dean and Stark device to remove the Water of the salt formation.

The benzene was then distilled ofl, the residue was dis- 10 lated in the same way as product of Example 7 and applied as described.

The compounds of Formula I (R =H) were tested by the following procedure.

The following crops were sown in boxes: sugar beet,

solved in acetone (150 cc.) and cooled to Acrylyl cabbage, carrots, peas and oats and the following standchloride (13.8 g.) was added below 5 and the solution ard weeds: fat hen, shepherds purse, poppy, chickweed, was stirred for 2 hrs. at 0. The mixture was then allowed annual meadow grass. The esters were dissolved in a to stand overnight. It was then refluxed for 2 hrs. cooled suitable solvent to which an emulsfying agent was added, to room temperature, the inorganic material was filtered diluted to the required concentration with water and apoif and the acetone was distilled off from the filtrate. plied to the boxes at a rate of 2 lbs. of the active ester The residue was diluted with benzene (150 cc.) and m 40 gallons of water per acre on the day of the sowing. washed with 5% aqueous solution of potassium carbonate Artificial rain equivalent to A" rain was then applied. 4 portions f 75 h) d h i h Water (4 r- The effect of this treatment was assessed after 21 days. tions of 75 cc. each). The benzene solution was then T e results are shown in Table I. dried over anhydrous sodium sulphate, filtered, and the Weed control 1s expressed as follows: solvent distilled off from the filtrate. The residue was C=Complete recrystallised from petroleum, B.P. 6080. 2,4-dinitro- =g 6-t-butylphenyl acrylate was obtained as pale yellow =m rate cubes, weighing 39.9 g. (90% of theory) and melting at =P 101-102 (Found: N, 9.7, (3 ,11 ,350 requires; N, control 5% Crop damage 1s expressed as follows:

This compound was formulated in the same way as 5:119 damage product of Example 7 and applied as described. 4=S11ght damage 3=moderate damage =severe damage EXAMPLE 10 1=very severe damage 0=complete kill 2,4-dinitro-6-t-butylphenyl methacrylate I th following T m IV h i i f h 2 441- nitro-6-s-amyl compound of Formula I (R =H) is given 2,4-d1n1tro-6-t-butylphenol (33.6 g.) Was dlssolved in for comparative purposes only.

TABLE IV Weed Crop hep- Annual G-alkyl Fat herds Ohick- Meadow Sugar Cabgroup R1 Hen Purse Poppyweed Grass beet bage Carrots Peas Oats t-Butyl Methyl C C C G P 4 2 4 5 5 Do. a-Ohloromethyl C O O M M 5 2 3 5 5 Do. a-Ohloroethyl O C M G M 5 3 3 5 5 o 1n C C G N 5 2 4 4 5 C C M N 5 5 3 5 5 s-Amy1 Methyl N M N M N 5 5 5 5 5 Do a-Gh10r0methy1 P M N N P 5 5 4 5 5 130."- Vinyl P O C N N 5 5 5 5 5 Do Isopropenyl P G N N P 5 5 2 5 5 s-Butyl. Methyl M 0 P G P 4 4 5 5 5 benzene (280 cc.), and pyrid e g-) was added to A further series of tests were conducted to compare the solution. The mixture was heated to reflux on a steamthe pre-emergence herbicidal activity of 2,4-dinitr0-6- tert. bath and methacrylyl chloride (14.63 g.) was added butylphenol esters of Formula I (R =H) and the correthrough the condenser. The solution was refluxed for sponding esters of 2,4-dinitro-6-sec. butyl-phenol. Th 1% hrs. and allowed to stand overnight at room temperatests were conducted in like manner to these described ture. The pyridine hydrochloride that precipitated was above except that the kill of weeds were expressed filtered ofl and the benzene was washed with 5% potasdiflerently i.e. the actual weeds in the boxes that survived sium carbonate (4 portions of 50 cc. each) and water the treatment were counted and the percentage of total (3 portions of 50 cc. each). The benzene was dried over weed control expressed as: anhydrous sodium sulphate, filtered, and the solvent dis- B tilled off from the filtrate. The residue weighing 42.2 g. 1O0 100 was crystallised from petroleum, B.P. 40-60. 2,4-dinitrou 6-t-butylphenyl methacrylate was obtained as white where rhomboidal needles, weighing 35.6 g. (82.8% yield) and BuzNumber of weeds i untreated boxes melting at s0-s1.s% (Found: N, 8.94. 0 .11 .14 0., re- Bt=Number of Weeds treated bOXeS- quires bl, 9.09% Crop damage was estimated as before. The results are 2,4-d1n1tro-6-t-butylphenyl methacrylate was formushown in Table V.

TABLE V Weed Crop Percent Shep- Annual Total fi-alkyl Fat herds Ground- Ohick- Meadow Total weed Sugar Cab- Cargroup RI hen Purse sel Poppy Weed Grass Others weeds control beet bage rots Peas Oats t-Butyl a-OhloromethyL 2 0 1 0 s 33 15 59 72 4.5 1.0 5.0 4.5 5.0 Do urChloroethyLu 0 0 0 0 5 38 s 51 4 5 2.5 4.5 3.5 5.0 Do Vinyl 0 0 0 0 2 32 8 42 5.0 1.5 4.5 5.0 5.0 Do Isopropenyl 1 0 1 0 11 33 14 6O 72 5.0 1.0 4.5 4.5 5.0 Do Prop-l-enyl- 0 0 1 0 4 53 17 75 65 5.0 1.5 4.0 5.0 5.0 s-Butyl wchloromethyL 0 0 4 1 2s 4s 20 101 52 5 0 3.0 4.5 4.5 5.0 Do a-Chloroethyl 2 0 7 0 24 43 31 107 49 5.0 4.0 4.5 5.0 4.0 D0 Vinyl 4 1 6 0 20 55 28 114 46 5.0 3.5 4.5 5.0 5,0 Do Is0pr0penyl- 0 0 s 0 24 45 1s 55 4.0 4.5 5.0 5.0 5.0 Do Prop-l-enyl 2 0 5 0 29 3e 21 03 56 5.0 5.0 5.0 5.0 5.0 Untreated 10 30 26 19 36 46 44 211 4.5 4.5 4.5 4.5 5.0

1 1 SELECTIVE HERBICIDAL TRIALS The following trials include, in addition to P1488, also P1101 and P1108.

Rates All applied at 50 gallons per acre, sprayer starting at the full rate and diluting down to A of that rate at the end of the 36 yd. run.

Assessment Weed counts were taken from 100 sq. in. of plot, at three positions in each treated strip, and at corresponding positions in the untreated strips. Hence in the tables are given the appropriate three rates for these positions.

TABLE VL-WEEDS AS FRACTION OF UN'lREA'lEl) Shephcrds Fat hen Chick- Annual purse (Cap- (Chcnopo- Groundsel weed nettle sellabursadiam (Scnccio (Stellaria (Urtica '1reatmontpomcro pasioris) album) tulgaris) media) wens) Veronica Grasses Others Total P1488 Misc. at

, 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 P1488 WP. at-

411) l! i 9 9 9 9 E 9 2 16 16 2 4 (3 0 2 2 48 2 2 2 2 2 2 2 2 2 2 2 2 P1488/Propha1n at-- 2 2 2 2 2 2 2 2 22 112 11) 2 2 2 g g g g g 2 2 2 2 2 2 2 2 2 11488/End0tlial/Propham at- P1488 25% wettable powder-This was prepared as described in Example 1.

P1488/Propham in the ratio of 2 parts P1488 to 3 parts propham. (All parts by weight.)

17.1 parts of P1488, 25.65 parts of propham, 5 parts of calcium salt of lignin sulphonic acid and 1 part of technical lauryl sodium sulphate were ground and mixed intimately with 51.25 parts of speswhite (a fine grade of China clay). This was made up with water, on stirring, to the required concentration.

P1488/Endothal/Propham in the ratio of 2 parts P1488 to 1 /2 parts endothal to 3 parts propham. (All parts by weight.) 17.1 parts of P1488, 10 parts of a fine diatomaceous earth, 24.04- parts of speswhite, 25.65 parts of propham, 2.5 parts of speswhite on which was adsorbed 20% of a non-ionic wetter (a polyoxyethylene glycol condensate), 5 parts of disodium salt of methylene dinaphthalene sulphonic acid and 15.71 parts of technical 61.1% endothal were intimately ground and mixed. This was made up with water, on stirring, to the required concentration.

Method of application:

Overall application by logarithmic sprayer.

Layout One unreplicated, randomized block of treated strips alternating with untreated strips each strip being 2 yds. wide and 36 yds. long.

The sugar beet was unaffected by the treatments.

P1108 7.5% Misc.--7.5 parts by weight of P1108 and 20 parts by weight of a mixture of anionic and non-ionic emulsifying agents were made up to parts by volume with heavy naphtha. This 7.5 w./v. solution was made up with water, on stirring, to the required concentration.

P1108 25 wettable powder (Parts are by weight) 25 parts of P1108 were intimately ground with 68.75 parts of speswhite 0.25 parts of technical lauryl sodium sulphate and 6 parts of calcium salt of lignin sulphonic acid.

P1108/Propham.This was formulated as in the case of P1488/Propham but using P1108 in place of P1488.

P1108/Endothal/Propham in the ratio of 1 part of Pl1O8:l /2 parts of end0thal23 parts of propham. (All parts by weight.)

8.55 parts of P1108, 10 parts of a fine diatomaceous earth, 32.59 parts of speswhite, 25.65 parts of propham, 2.5 parts of speswhite on which was adsorbed 20% of a non-ionic wetter (a polyoxyethylene glycol ether condensate), 5 parts of disodium salt of methylene dinaphthalene sulphonic acid and 15.71 parts of technical 61.6% endothal were intimately ground and mixed.

P1108/Endothal/Propham (2:1A2:3).-This was formulated as in the case of P1488 but using P1108 instead of P1488.

TABLE VIL-WEEDS AS A FRACTION OF UNTREATED Shepherd's Fat hen Chick- Annual iffiafiifii 2253; Zfiiiii (22223233; (25222 Treatment per acre pastoris) album) mlgaris) media) wens) Veronica Grasses Others Total P1108 7.5% Misc. alt- 2 2 2 2 2 2 2 .2 2 1b 2 2 2 2 2 2 2 2 1% 1b 2 2 2 2 2 2 2 2 2 P1108 WP. at- 2 2 2 2 2 2 2 2 2% 1b 2 2 2 2 2 2 2 2 1b 2 2 2 2 2 2 2 2 2 PllOB/Propham atefilb --l 2 2 2 2 2 2 I-I 3 2 --l 23 2% 2 2 f2 2 2 2 2? W12 --l 2 2i 2 2 2 2 8 2 2% PllOS/Endothal/Propham et- 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 P1108/Endothal/Propham at- P1101 (2,4 dinitro 6-t-butylphenyl acrylate).-The higher rates i.e. 4 lb. and 2% lb. of P1101 per acre were damaging to the sugar beet. The lower rate gave, however, excellent control of weeds and was completely safe to the sugar :beet. 1

Formulation of P1101 P1101 20% Misc.20 parts 'by weight of P1101 and 20 parts by weight of a mixture of anionic and non-ionic emulsifying agents were made up to 100 parts by volume with heavy naphtha to give a 20% w./v. solution. This TABLE VIII.WEEDS AS FRACTION OF UNTREATED Shepherds Fat hen Chick- Annual purse (C'ap- (Chenopo- Groundsel weed nettle sellaburea dium (Seneci 0 (Stellan'a (Urtica Treatment per acre pllStOTHi) album) vulgarie) media) wens) Veronica Grasses Others Total P1101 2 Mlsc at 1,211) o 14 3 2 4 0 0 5 5g 0 0 0 0 0 0 0 0 0 P. P1101 23% W at 1221b 6 12 7 5 3 1 1 3 38 0 2, 2 2 0 0 0 0 6 P1101/Propham at %.2 lb T6 T7 5 5 g 6 6 5 E 0 2 2 0 0 0 0 0 4 P1 01 P 1 :2 1 I mpham at 1b 7 1s 1 4 14 0 0 T 45 0 0 0 0 0 0 0 0 0 Pl/End0thal/Propham at 1%.1.21b E E 5T 2 g I a 0 12 0 2 0 0 0 0 14 t l P h 2 :1 b ha] mp am 51 4 12 2 2 2 0 2 e 30 16 The results reported in Tables VI, VII and VIII should 2. Z-t-butyl-4,6-dinitro-5-methylphenyl acetate. be compared with results for the commercial mixture of 3. 2-t-butyl-4,6-dinitro-5-methylphenyl u-chloroacetate. endothal and propham at 2 /2 lb. of endothal and 1 /2 lb. 4. 2-t-butyl-4,6-dinitro-5-methy1phenyl acetate. of propham per acre (foot of Table VIII). 5. 2 t butyl-4,6-dinitro-S-methylphenyl a-chloropro- What is claimed is: 5 pionate. 1. A compound of the formula: 6. 2-t-buty1-4,6-dinitro-S-rnethylphenyl methacrylate.

Co B References Cited (GHmC NO; UNITED STATES PATENTS 10 2,802,883 8/1957 Dietzler 260-622 3,123,522 3/1964 Scherer et al 26O479 N0, LORRAINE A. WEINBERGER, Primary Examiner.

in which R is selected from the group consisting of M. G. BERGER, Assistant Examiner. methyl, alkenyl of not more than 3 carbon atoms, a-

chloroalkyl of not more than 2 carbon atoms and a-chloro- US. Cl. X.R. alkenyl of not more than 3 carbon atoms. 71-106; 260-622 

